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KOMITE NASIONAL KESELAMATAN TRANSPORTASI
REPUBLIC OF INDONESIA
2016
FINAL
KNKT.14.03.09.04
KOMITE
NASIONAL
KESELAMATAN
TRANSPORTASI
PT. Wings Abadi Air
ATR 72-212A; PK-WFR
Sultan Hasanuddin Airport, Makassar
Republic of Indonesia
28 March 2014
Aircraft Serious Incident Investigation Report
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This final investigation report was produced by the Komite Nasional
Keselamatan Transportasi (KNKT) 3rd
Floor Ministry of Transportation,
Jalan Medan Merdeka Timur No. 5 Jakarta 10110, Indonesia.
The report is based upon the investigation carried out by the KNKT in
accordance with Annex 13 to the Convention on International Civil
Aviation Organization, the Indonesian Aviation Act (UU No. 1/2009) and
Government Regulation (PP No. 62/2013).
The final report consists of factual information collected until the final
report published. This report includes analysis and conclusion.
Readers are advised that the KNKT investigates for the sole purpose of
enhancing aviation safety. Consequently, the KNKT reports are confined to
matters of safety significance and may be misleading if used for any other
purpose.
As the KNKT believes that safety information is of greatest value if it is
passed on for the use of others, readers are encouraged to copy or reprint
for further distribution, acknowledging the KNKT as the source.
When the KNKT makes recommendations as a result of its
investigations or research, safety is its primary consideration.
However, the KNKT fully recognizes that the implementation of
recommendations arising from its investigations will in some cases
incur a cost to the industry.
Readers should note that the information in KNKT reports and
recommendations is provided to promote aviation safety. In no case is
it intended to imply blame or liability.
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TABLE OF CONTENTS
TABLE OF CONTENTS ........................................................................................................ i
TABLE OF FIGURES ......................................................................................................... iii
ABBREVIATIONS AND DEFINITIONS .......................................................................... iv
INTRODUCTION ................................................................................................................. vi
1 FACTUAL INFORMATION ......................................................................................... 1
1.1 History of the Flight............................................................................................... 1
1.2 Personnel Information ........................................................................................... 2
1.2.1 Pilot in Command ..................................................................................... 2
1.2.2 Second in Command ................................................................................ 2
1.3 Aircraft Information............................................................................................... 3
1.4 Meteorological Information ................................................................................... 3
1.5 Aerodrome Information ......................................................................................... 4
1.6 Flight Recorders..................................................................................................... 4
1.6.1 Flight Data Recorder ................................................................................ 5
1.6.2 Cockpit Voice Recorder ........................................................................... 7
1.7 Wreckage and Impact Information ........................................................................ 7
1.8 Organization information....................................................................................... 8
1.8.1 Company Operation Manual .................................................................... 8
1.8.2 Operation Training Manual (OTM) ......................................................... 9
1.8.3 QRH (Quick Reference Handbook) ....................................................... 10
1.8.4 FCTM (Flight Crew Training Manual) .................................................. 10
1.9 Additional Information ........................................................................................ 10
1.9.1 Crosswind During Landing .................................................................... 10
1.9.2 Situational Awareness and Decision Making ......................................... 11
1.9.3 Thunderstorm formation ......................................................................... 12
2 ANALYSIS ..................................................................................................................... 15
2.1 Flight Technique on crosswind landing ............................................................... 15
2.2 Decision Making .................................................................................................. 16
3 CONCLUSION .............................................................................................................. 17
3.1 Findings ............................................................................................................... 17
3.2 Contributing Factors ............................................................................................ 18
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4 SAFETY ACTION ........................................................................................................ 19
5 SAFETY RECOMMENDATIONS ............................................................................. 20
5.1 PT. Wings Abadi Air ........................................................................................... 20
5.2 The Directorate General of Civil Aviation (DGCA) ........................................... 20
6 APPENDICES................................................................................................................ 21
6.1 Notice to Pilot ...................................................................................................... 21
6.2 The ATR Safety Note .......................................................................................... 22
6.3 Direct Involves Parties Comments ...................................................................... 24
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TABLE OF FIGURES
Figure 1: The wind information recorded on the AWOS at the time of the aircraft landing . 4
Figure 2: Graph of the FDR data started from prior to touch down ....................................... 5
Figure 3: The marks of the wheel where started to turn right ................................................ 7
Figure 4: The marks of the wheel where started left the runway pavement ........................... 8
Figure 5: Weathervane.......................................................................................................... 11
Figure 6: Tail wheel airplane ................................................................................................ 11
Figure 7 : Nose wheel airplane ............................................................................................. 11
Figure 8: Decision Making Model Wickers and Flach (1988) ............................................. 12
Figure 9: Stages of thunderstrom.......................................................................................... 13
Figure 10: Lateral view illustration of thunderstorm ........................................................... 13
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ABBREVIATIONS AND DEFINITIONS
AAL : Above Aerodrome Level
A/C : Aircraft
ADC : Air Data Computer
AHRS : Altitude and Heading Reference System
ANS : Approach Non Stabilized
AOC : Air Operator Certificate
ARFF : Airport Rescue and Fire Fighting
ATC : Air Traffic Control
ATIS : Aerodrome Terminal Information Services
ATPL : Air Transport Pilot License
ATR : Avions de Transport Regional
ATS : Air Traffic Service
AWOS : Automated Weather Observation Services
BMKG : Badan Meterologi Klimatologi dan Geofisika (Metrological
Climatology and Geophysical Agency)
°C : Degrees Celsius
CASR : Civil Aviation Safety Regulation
C/L : Check List
C of A : Certificate of Airworthiness
COM : Company Operation Manual
CPL : Commercial Pilot License
C of R : Certificate or Registration
CRM : Crew Resources Management
CSN : Cycles Since New
CVR : Cockpit Voice Recorder
DGCA : Directorate General of Civil Aviation
DME : Distance Measuring Equipment
ECU : Electronic Control Unit
EEC : Engine Electronic Control
EFIS : Electronic Flight Instrumentation System
ENG : Engine
EVAC : Evacuate
GPWS : Ground Proximity Warning System
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FA : Flight Attendant
FCOM : Flight Crew Operation Manual
FCTM : Flight Crew Training Manual
FDR : Flight Data Recorder
FL : Flight Level
ft : Feet
GNSS : Global Navigation Satellite System
ICAO : International Civil Aviation Organization
ILS : Instrument Landing System
Kg : Kilogram(s)
Km : Kilometer(s)
KNKT : Komite Nasional KeselamatanTransportasi
kt : Knot (s) (nm/hours)
LT : Local Time
LTM : Long Term Memory
MAC : Mean Aerodynamic Chord
mbs : Millibar(s)
Nm : Nautical mile(s)
OTM : Operation Training Manual
PF : Pilot Flying
PIC : Pilot in Command
PNF : Pilot Non Flying
SCT : Scattered
SGU : Symbol Generator Unit
SIC : Second in Command
SID : Standard Instrument Departure
SSFDR : Solid State Flight Data Recorder
STM : Short Term Memory
T/O : Take off
UTC : Universal Time Coordinate
VOR : Very High Frequency Omni Directional Range
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INTRODUCTION
SYNOPSIS
An ATR 72-500, registered PK-WFR, on 28 March 2014 was being operated by PT. Wings
Abadi Air, as scheduled passenger flight. The aircraft departed Pomala Airport, Sulawesi
Tenggara at 0710 UTC (1510 LT) to Sultan Hasanuddin Airport, Makassar, Sulawesi Selatan.
On board in this flight were two pilots, two flight attendants and 73 passengers. The Second
in Command (SIC) acted as Pilot Flying (PF) and the Pilot in Command (PIC) acted as Pilot
Non Flying (PNF).
The pilot elected to fly via MKS VOR to avoid cumulonimbus cloud on the south east area
from Makassar. The flight then vectored for Instrument Landing System (ILS) approach
runway 03.
At 1500 feet, the Hasanuddin Tower controller and was provided the landing clearance with
additional information of wind which was from 120° up to 23 knots. Refer to the information
from the controller and considered the experience of the SIC, the PIC took over the control of
the aircraft and the SIC performed the duty as PNF.
The PIC noticed that on the right side of the final course was dark and thick cloud, while on
the left was clear.
At 08.00 UTC, the aircraft touched down normal on the touchdown zone. The pilot started to
applied the brake and reverse the propeller. The FDR recorded that after touchdown, left
rudder was applied gradually from 3° up to 27° and the aircraft heading was varied between
026° to 031°. The application of left rudder reduced and changed to right rudder up to 26° and
the aircraft heading changed from 030° to 074°. The aircraft then run off to the right of the
runway. The aircraft skid and veered to the right and stopped at 15 meters from the runway
pavement.
No one injured in this serious incident. The aircraft suffer minor damage mainly on the
landing gear doors.
The investigation concluded that the incorrect rudder application to compensate the crosswind
affect had resulted in the aircraft exiting the runway. This might due to the pilot confusion to
the crosswind effect as result of inadequate training.
At the time of issuing this final investigation report, the Komite Nasional Keselamatan
Transportasi (KNKT) has been informed safety action of the PT. Wings Abadi Air.
Following this investigation, KNKT issued safety recommendations addressed to PT.Wings
Abadi Air and the Directorate General Civil Aviation (DGCA).
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1 FACTUAL INFORMATION
1.1 History of the Flight
An ATR 72-500, registered PK-WFR, on 28 March 2014 was being operated by PT.
Wings Abadi Air, as scheduled passenger flight. The aircraft departed Pomala
Airport, Sulawesi Tenggara at 1510 LT (0710 UTC1) to Sultan Hasanuddin Airport,
Makassar 2 , Sulawesi Selatan. On board the aircraft were two pilots, two flight
attendants and 73 passengers.
The Second in Command (SIC) acted as Pilot Flying (PF) and the Pilot in Command
(PIC) acted as Pilot Non Flying (PNF). The flight cruised on altitude of 14,000 feet.
While approaching Makassar, the pilots received weather information from the
Aerodrome Terminal Information Services (ATIS), contained information of the
wind was from 230° and the velocity 8 knots, visibility 10 km, cloud scattered (SCT)
with the cloud base 1,900 feet, temperature 32°C and dew point 25°C, and the
aerodrome pressure 1,009 millibars.
The pilot elected to fly via MKS VOR to avoid cumulonimbus cloud on the south
east area from Makassar. The flight then vectored for Instrument Landing System
(ILS) approach runway 03. Ahead of the flight were two aircrafts on approach for
landing and after those aircrafts landed, the flight was cleared for ILS approach
runway 03. There was no report from pilots of both previous flights related to the
weather condition on approach.
At altitude of 1,500 feet, the flight was transferred to Hasanuddin Tower controller
and was provided the landing clearance with additional information of wind which
was from 120° up to 23 knots. The PNF checked the wind indication on the Global
Navigation Satellite System (GNSS) and found that the wind was from the right and
slightly tail wind with velocity between 11 to 15 knots.
Refer to the information from the controller and considered the experience of the
SIC, the PIC took over the control of the aircraft and the SIC performed the duty as
PNF.
The PIC noticed that on the right side of the final course was dark and thick cloud,
while on the left was clear.
At 0800 UTC, the aircraft touched down within the touchdown zone. The pilot
started to applied the brake and reverse the propeller. The aircraft decelerated and
when the aircraft speed was approximately 70 knots, the pilot felt that the aircraft
suddenly veered to the right. The pilot attempted to recover the situation by applied
differential rudder and nose wheel steering. The pilot felt that the nose wheel steering
was heavier than normal.
The aircraft skid and veered to the right and stopped at 15 meters from the runway
pavement. After the aircraft completely stop, the pilot notified the tower controller
that the aircraft stopped outside the runway and requested assistance.
The Flight Attendant (FA) waited for the command from the PIC in case evacuation
was required. After few seconds later and there was no command from the PIC, the
1 The 24-hour clock used in this report to describe the time of day as specific events occurred is in Coordinated Universal Time (UTC).
Local time that be used in this report is Waktu Indonesia Barat (WIB) which is UTC + 7 hours.
2 Sultan Hasanuddin Makassar Airport will be named as Makassar for the purpose of this report.
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FA-13, checked the outside condition. She found that outside area was grass and the
aircraft tilted to the right. She then pressed the “EMERGENCY” button to call to the
pilots. The FA-1 then announced to the passengers to keep calm. This announcement
also triggered the FA-2 to start perform the duty.
After the engines shut down, the FA-1 contacted the pilot afterward the PIC went out
the cockpit, then opened the crew entrance door and disembarked the aircraft to
check the outside area. The PIC then commanded the flight attendant to evacuate the
passengers.
The Airport Rescue and Fire Fighting (ARFF) team arrived on the site and ready to
assist the passenger evacuation. After knowing that the ARFF has arrived, the flight
attendants opened the passenger door and passengers disembark normally and
transferred to passenger terminal.
No one injured in this serious incident. The aircraft was minor damaged, mainly on
the landing gear doors.
1.2 Personnel Information
1.2.1 Pilot in Command
The PIC was 43 years old Indonesia pilot and has joined the company since 2008.
The pilot held valid ATP License (Air Transport Pilot License) issued on 10 May
2010 and rated for ATR aircraft. The pilot held first class medical certificate which
valid until 02 July 2014 with limitation of “holder shall posses glasses that correct
for near vision”. The pilot has performed line check on 19 January 2014 and last
simulator proficiency check was performed on 30 October 2013.
The PIC flying experience
Total hours : 7713 hours
Total on type : 2579 hours
Last 90 days : 262 hours 55 minutes
Last 60 days : 176 hours 10 minutes
Last 24 hours : 2 hours 15 minutes
This flight : 45 minutes
1.2.2 Second in Command
The SIC was 24 years old Indonesia pilot and has joined the company since 2013.
The pilot held valid CP License (Commercial Pilot License) issued on 27 November
2012 and rated for ATR aircraft. The pilot held first class medical certificate which
valid until 22 July 2014 without limitation. The pilot has performed line check on 20
August 2013 and last simulator proficiency check was performed on 11 April 2013.
The SIC flying experience
Total hours : 881 hours 1 minutes
Total on type : 597 hours 15 minutes
3 Flight Attendant (FA) – 1 is the leader of the flight attendants, responsible for the safety of the passengers.
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Last 90 days : 249 hours 15 minutes
Last 60 days : 183 hours 55 minutes
Last 24 hours : 2 hours 15 minutes
This flight : 45 minutes
During the interview both pilot described their confusion of the right crosswind
effect to the fact that the aircraft veered to the right. In their opinion the aircraft
would have been veered to the left as the effect of the cross wind from the right.
1.3 Aircraft Information
The aircraft was France manufactured ATR 72-500, registered PK-WFR. It has valid
Certificate of Airworthiness (C of A) and Certificate or Registration (C of R) and has
accumulated 7,666 hours and 58 minutes of total flight hours and 8,299 cycles since
new.
The aircraft departed with the total takeoff weight of 21,620 kg which was 480 kg
below the maximum allowable takeoff weight. The takeoff Mean Aerodynamic
Chord (MAC) was 23.37 % which was within the range limit of 16 – 37 %. The
aircraft was operated within the approve weight and balance limits.
The aircraft was airworthy prior to the occurrence.
1.4 Meteorological Information
The weather of Makassar reported on the Aerodrome Terminal Information Services
(ATIS) at 0730 UTC was as follows:
Wind : 230° / 08 knots
Visibility : 10 km
Cloud : SCT 1,900 feet
Temperature : 32°C
Dewpoint : 25°C
Pressure : 1,007 mbs
The Makassar was equipped with Automated Weather Observation Services
(AWOS) and the data was displayed at Badan Meteorology Klimatology dan
Geofisika (BMKG – The Agency of Meteorology, Climatology and Geophysics)
office and Makassar Tower control station. The data indicated that at 0800 UTC, the
wind changed from direction of 220° with velocity of 7 knots to direction of 130°
with velocity more than 18 knots (figure 1).
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Figure 1: The wind information recorded on the AWOS at the time of the aircraft
landing
1.5 Aerodrome Information
Airport Name : Sultan Hasanuddin Airport
Airport Identification : WAAA / UPG
Airport Operator : PT. Angkasa Pura I
Airport Certificate : 017/SBU-DBU/VII/2010
Coordinate : 05º 03’39”S 119º33’16”E
Elevation : 47 feet
Runway Direction : 13/31 and 03/21
Runway Length : 2,500 meters
Runway Width : 45 meters
Surface : Concrete Asphalt
1.6 Flight Recorders
The aircraft was equipped with a Flight Data Recorder (FDR) and Cockpit Voice
Recorder (CVR). Both recorders were examined in the KNKT facility in Jakarta.
Both recorders contained good quality data including the serious incident flight data.
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1.6.1 Flight Data Recorder
The Flight Data Recorder (FDR):
Manufacturer : L3 Comm
Part Number : 2100-4043-00
Serial Number : 000677687
Figure 2: Graph of the FDR data started from prior to touch down
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UTC
Tim
e (s
eco
nd
s)
Pre
ssu
re A
ltit
ud
e (f
eet
)
Rad
io H
eigh
t (f
eet)
Gro
un
dsp
eed
(kn
ots
)
Mag
net
ic H
ead
ing
(deg
rees
)
GR
OU
ND
AIR
(d
iscr
ete
)
Co
mp
ute
d A
irsp
eed
(kn
ots
)
Win
d D
irec
tio
n (
deg
rees
)
Win
d S
pee
d (
kno
ts)
Hea
d W
ind
(kn
ots
)
Thro
ttle
Lev
er P
os
Engi
ne
1 (
deg
rees
)
Torq
ue
Engi
ne
1 (
%)
Torq
ue
Engi
ne
2 (
%)
Bra
ke P
ress
ure
(p
si)
Ru
dd
er P
edal
Po
s (d
egre
es)
Ru
dd
er P
osi
tio
n (
deg
rees
)
Co
ntr
ol W
hee
l Po
s (d
egre
es)
167 10 113 32 AIR 108
53 36 32.5 7 4 4 3
168 5 114 32 AIR 111
6 4 49 37 33.25 7 4 4 6
165 2 114 31 AIR 112 110
48 36 32.5 7 1 -2 -19
7:50:04 158 0 114 31 AIR 105
38 34 28.25 12 5 6 -18
171 -1 114 32 AIR 109
25 22 9.5 6 7 11 -23
152 -1 113 31 GRD 98
8 1 17 5 3.75 5 8 15 -30
133 -1 112 28 GRD 102 94
16 10 12.25 9 -1 -3 -21
7:50:08 135 -1 104 26 GRD 99
18 19 20.25 5 -8 -26 -31
140 -1 100 30 GRD 85
19 18 15.75 11 -8 -27 -58
127 -1 96 39 GRD 84
0 0 19 15 13.25 6 0 -5 -15
133 -1 90 52 GRD 72 0
19 14 12 0 8 15 17
8:50:12 158 -1 85 63 GRD 80
19 12 11 112 12 26 7
166 -2 78 72 GRD 66
19 12 10.25 22 0 26 5
156 -2 73 74 GRD 63
0 0 19 11 9.5 22 13 26 -18
156 -1 68 70 GRD 70 0
19 10 8.75 28 12 26 -17
8:00:16 172 -1 62 58 GRD 55
21 9 8.25 33 10 26 32
174 -2 56 38 GRD 40
12 8 7.25 28 9 24 23
201 -2 46 19 GRD 39
0 0 28 8 10.5 22 9 26 54
182 -1 38 6 AIR 25 0
25 14 7 29 9 26 63
8:00:20 195 -1 28 359 AIR 17
25 10 6 27 9 26 0
200 -1 16 358 AIR 14
25 10 6 26 10 26 62
189 -1 2 358 GRD 4
0 0 20 9 6 28 10 26 58
189 -2 0 358 GRD 8 0
20 8 6 27 10 26 54
8:00:24 192 -2 0 358 GRD 3
20 8 6.75 28 10 26 52
Table 1: FDR table data of significant parameters from prior to touchdown
until the aircraft stop
The FDR data showed:
1. Prior to touchdown the wind was easterly with wind velocity up to 8 knots.
2. Aircraft touched down normally.
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3. After touchdown, engine torque equally increased and then reduced.
4. The left rudder was applied (negative value on the FDR) then changed to right
rudder.
5. Aircraft heading increased (turn right) in four seconds up to heading 074 or
approximately 44 degrees from runway bearing.
6. No significant brake pressure recorded.
7. The aircraft stopped on heading north.
1.6.2 Cockpit Voice Recorder
The Cockpit Voice Recorder (CVR)
Manufacturer : L3 Comm
Part Number : 2100-1020-02
Serial Number : 000672133
The CVR did not record pilot conversation during the aircraft on descend. The CVR
recorded pilot and ATC communication. The significant excerpts of the CVR data are
as follows:
Time
(UTC) Communication
7:56:10 Flap selected to 30
7:56:24 Before landing checklist initiated
7:57:19 The PIC confirming that the wind was cross wind from the right
7:57:50 Controller issued landing clearance and informed that the wind was
120° up to 23 knots.
7:59:05 The aircraft touched down
1.7 Wreckage and Impact Information
The wheel tracks were found on runway 03, begin on the touchdown and were on the
runway centre line. The marks turn to the right at approximately 45º from the runway
direction.
Figure 3: The marks of the wheel where started to turn right
Left main wheel
marks
Right main wheel
marks
Nose wheel marks
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Figure 4: The marks of the wheel where started left the runway pavement
1.8 Organization information
1.8.1 Company Operation Manual
4.10.6 APPROACH AND LANDING
4.10.6.1 Crew Coordination during Holding, Approach and Landing
During these phases of flight, both pilots must be seated in their assigned cockpit
seats. Careful planning of the approach and close cooperation between flight crews
is necessary to achieve a safe approach and landing. The techniques and procedures
to be used shall be discussed in advance, in order to avoid errors and
misunderstandings. Both pilots shall therefore familiarize themselves thoroughly
with the relevant data such as descent altitude restrictions, weather conditions,
aircraft serviceability, ground facilities, holding and approach procedures runway
data, missed approach procedures etc. The crew briefing should be completed well
in advance of terminal area penetration and be updated if changing circumstances
so require.
Normally the PF, programs and monitors the auto-pilot/flight director and
autothrottle, and gives the necessary commands (e.g. checklist, gear down, flaps etc).
The PNF, monitors the approach, keeps lookout, executes the allocated system
operation on command of the PF and confirms its execution, does the radio
communication and checks for visual reference. The PNF therefore, shall be fully
familiar with the intentions of the PF, and shall have facts and figures ready when
needed. The use of facilities shall be planned beforehand, and on passing one
facility, the PNF shall inform the PF and be ready to retune to the next facility
immediately. During the descent phase, at altitudes below approximately 10.000 feet,
and during taxi, all flight crewmembers shall concentrate on cockpit procedures,
cockpit monitoring and lookout, and refrain from non-essential matters.
Right main wheel
marks
Left main wheel
marks
Nose main wheel
marks
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1.8.2 Operation Training Manual (OTM)
The OTM Chapter 5.5 ATR 72-500 Pilot type rating training shows that the pilots
had been trained for the cross wind landing twice which were on session 4 and
session 5.
The OTM Chapter 5.5 ATR 72-500 Pilot type rating training
Type Rating Simulator Session 4
Briefing ................................................................................ 1 hour
Exercises............................................................................... 4 hour
1. Internal inspection – Preliminary cockpit preparation
2. Final Cockpit Preparation – Before taxi – Taxi – before TO C/L
3. TAKE OFF – Climb sequence – After TO C/L
4. Climb on SID to FL 9000 feet
5. AFCS utilisation AP ON and AP OFF with FD
6. Configuration changes as needed
7. ARRIVAL preparation (weather, datacard, arrival briefing)
8. ILS APPROACH
9. GO AROUND – Radar Vector
10. VOR DME approach
11. Cross wind LANDING
12. After Landing – DYNAMIC ENG TEST, Parking, Leaving the A/C C/L
Debriefing ............................................................................ 1 hour
Session 5
Briefing ................................................................................ 1 hour
Exercises............................................................................... 4 hour
1. SHORT TRANSIT preparation – Final cockpit preparation – Before Taxi
2. Eng 1: NO ITT DURING ENG START then start A+B – Taxi – Before TO
3. Take Off – EFIS COMP (ROLL) – SID FL 8000 feet – Failure treatment
4. ENGINE FLAME OUT no.2 on cruise – SINGLE ENG HANDLING
5. RESTART IN FLIGHT
Stall with Ice accretion WITHOUT ICING AOA ON
Stall with Ice accretion WITH ICING AOA ON
6. Ice accretion – ACW BUS 2 OFF (ADC disagreement) (reset)
7. AHRS fail on PF side (reset)
8. CREW MEMBER INCAPACITATION
9. Radar Vector – ILS - Landing
10. VOR DME approach
11. Cross wind LANDING
12. Take Off – SGU FAIL (reset) – normal procedure – SID FL 8000 feet –Failure
Treatment
13. Take off – climb straight ahead 3000’ – ECU/EEC FAULT before
acceleration altitude – radar vector.
14. After failure treatment BOTH ECU/EEC FAULT
15. Vector for ILS keeping HIGH SPEED (190 kts) up to 2000’
16. ANS (Approach Non Stabilized) at 1000’ AAL – GO AROUND to 2000’ –
Freeze at the end of the C/L
17. Reposition A/C at TO to demonstrate BOT ECU/EEC FAULT effect on ground
Debriefing ............................................................................ 1 hour
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1.8.3 QRH (Quick Reference Handbook)
1.8.4 FCTM (Flight Crew Training Manual)
FCTM ATR 72-500 ABNORMAL AND EMERGENCY PROCEDURE, 03.02.01,
page 2 Sep 2012.
Part of the on ground evacuation procedure stated that evacuation command conducted by
the captain through public address and afterward switch off the battery.
1.9 Additional Information
1.9.1 Crosswind During Landing
When an airplane is airborne it moves with the air mass in which it is flying
regardless of the airplane's heading and speed. However, when an airplane is on the
ground it is unable to move with the air mass (crosswind) because of the resistance
created by ground friction on the wheels.
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Characteristically, an airplane has a greater profile or side area, behind the main
landing gear than forward of it. With the main wheels acting as a pivot point and the
greater surface area exposed to the crosswind behind that pivot point, the airplane
will tend to turn or "weathervane" into the wind (figure 5).
Though it is characteristic of most airplanes, this weathervaning tendency is more
prevalent in the tail wheel type because the airplane's surface area behind the main
landing gear is greater than in nose wheel type airplanes (see figure 6 and 7).
Wind acting on an airplane during crosswind landings is the result of two factors -
one is the natural wind which acts in the direction the air mass is traveling, while the
other is induced by the movement of the airplane and acts parallel to the direction of
movement. Consequently, a crosswind has a headwind component acting along the
airplane's ground track and a crosswind component acting 90º to its track. The
resultant or relative wind, then, is somewhere between the two components. As the
airplane's forward speed decreases during the after landing roll, the headwind
component decreases and the relative wind has more of a crosswind component. The
greater the crosswind component the more difficult it is to prevent weathervaning.
Figure 5: Weathervane Figure 6: Tail wheel airplane Figure 7 : Nose wheel airplane
In February 2014, the aircraft manufacturer issued the Safety Note "Be Prepared For
Crosswind Landing" to provide guidance to the pilots to perform crosswind landing.
This Safety Note particularly emphasizes the use of rudder during landing roll that
must be smooth, mainly for any upwind input. The detail of the Safety Note available
on the appendices of this report.
1.9.2 Situational Awareness and Decision Making
Relation between the Short Term Memory (STM) are the spatial orientation, ability
to process information, and emotional/physical condition, and the Long Term
Memory (LTM) is the experience, training, management skill, physical skill, and
personal attitude refers the figure below shows the process and relation of the input
cues assessment (diagnostic) includes the risk assessment decision making.
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Figure 8: Decision Making Model Wickers and Flach (1988)
1.9.3 Thunderstorm formation
Generally, thunderstorms require three conditions to form:
1. Moisture
2. An unstable air mass.
3. A lifting force (heat)
All thunderstorms, regardless of type, go through three stages: the cumulus stage,
the mature stage, and the dissipation stage. The average thunderstorm has a 24 km
(15 miles) diameter. Depending on the conditions present in the atmosphere, these
three stages take an average of 30 minutes to go through.
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Figure 9: Stages of thunderstrom
Figure 10: Lateral view illustration of thunderstorm
Cumulus Stage
The first stage of a thunderstorm is the cumulus stage, or developing stage. In this
stage, masses of moisture are lifted upwards into the atmosphere. The trigger for this
lift can be insolation heating the ground producing thermals, areas where two winds
converge forcing air upwards, or where winds blow over terrain of increasing
elevation. The moisture rapidly cools into liquid drops of water due to the cooler
temperatures at high altitude, which appears as cumulus clouds. As the water vapor
condenses into liquid, latent heat is released, which warms the air, causing it to
become less dense than the surrounding dry air. The air tends to rise in an updraft
through the process of convection (hence the term convective precipitation). This
creates a low-pressure zone beneath the forming thunderstorm. In a typical
thunderstorm, approximately 5×108kg of water vapor is lifted into the Earth's
atmosphere.
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Mature Stage
In the mature stage of a thunderstorm, the warmed air continues to rise until it
reaches an area of warmer air and can rise no further. Often this 'cap' is the
tropopause. The air is instead forced to spread out, giving the storm a characteristic
anvil shape. The resulting cloud is called cumulonimbus incus. The water droplets
coalesce into larger and heavier droplets and freeze to become ice particles. As these
fall they melt to become rain.
Dissipating Stage
In the dissipation stage, the thunderstorm is dominated by the downdraft. If
atmospheric conditions do not support super cellular development, this stage occurs
rather quickly, approximately 20–30 minutes into the life of the thunderstorm. The
downdraft will push down out of the thunderstorm, hit the ground and spread out.
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2 ANALYSIS
The investigation considered that the aircraft was not a factor. Air traffic controller
information of wind condition was a good practice to improve pilot awareness.
Therefore, the analysis will discuss the cause of the aircraft veered to the right and
the weather condition in the airport vicinity that might affect the aircraft and pilot
decision while on the landing roll.
2.1 Flight Technique on crosswind landing
Prior to approach on runway 03, the pilot noticed cumulonimbus clouds on the east
side of the airport and decided to avoid the area. During the approach the pilots also
noticed black and thick cloud on the right side of the approach path, while on the left
side was clear.
There was no report from any pilot related to the weather condition on approach area.
The controller notified the pilot of wind which was from 120° up to 23 knots or
perpendicular to the landing direction up to 23 knots. The wind indicated on the
GNSS was from the right and slightly tail wind with velocity between 11 to 15 knots.
Considering the wind condition and the experience of the SIC, the PIC took over the
control. The aircraft touched down normally.
The FDR recorded that after touchdown, left rudder was applied gradually from 3°
up to 27° and the aircraft heading was varied between 026° to 031°. The application
of left rudder reduced and changed to right rudder up to 26° and the aircraft heading
changed from 030° to 074°. The aircraft then run off to the right of the runway.
Prior and during the approach, there were several significant information of
cumulonimbus existence which were the visual view of the pilot to the cloud
formation and controller information of significant cross wind condition. There was
no pilot discussion recorded on the CVR to anticipate this condition. The only action
was that the PIC took over control of the aircraft.
After touchdown, the pilot initially applied left rudder and able to manage the aircraft
heading on runway bearing. The pilot then applied right rudder and the aircraft
turned to the right.
During the interview, the pilots explained their confusion of the effect of the wind.
They assumed that the aircraft would have been veered to the left as the effect of
right crosswind.
The shape of the vertical stabilizer will have greatest effect to the crosswind
condition. The vertical stabilizer and all part of the aircraft behind the main wheel
will be pushed by the air, hence the nose will move into the wind (weathervaning).
So, on a right crosswind, the aircraft will turn to the right. The right rudder
application would make the aircraft veered more to the right.
Misinterpretation of the pilot to the effect of crosswind might have led to incorrect
recovery action.
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2.2 Decision Making
The Company Operation Manual on 4.10.6 APPROACH AND LANDING 4.10.6.1
Stated that; Careful planning of the approach and close cooperation between flight
crews is necessary to achieve a safe approach and landing. The techniques and
procedures to be used shall be discussed in advance, in order to avoid errors and
misunderstandings. Both pilots shall therefore familiarize themselves thoroughly
with the relevant data such as descent altitude restrictions, weather conditions,
aircraft serviceability, ground facilities, holding and approach procedures runway.
In the dissipation stage of cumulonimbus, the thunderstorm is dominated by the
downdraft. The downdraft will push down out of the thunderstorm, hit the ground
and spread out.
The wind direction as recorded by AWOS changed from westerly to easterly and
increased in velocity. This related to the cumulonimbus which was existed
surrounding the airport.
Prior and during the approach, there were several significant information to the pilot
related to the existence of cumulonimbus such as dark and thick cloud on the right
side of the final course and strong crosswind condition.
The CVR recorded that the pilots noticed the crosswind condition, however there
was no discussion recorded concerning the anticipation to this condition. The only
action was that the PIC took over control of the aircraft.
The absence of pilot discussion related to the cumulonimbus existence as required by
the COM, most likely had reduced or absence the important information stored as
short term memory which might require for the pilot to make decision during the
approach and landing roll.
The OTM Chapter 5.5 ATR 72-500 Pilot Type Rating Training shows that the pilots
had been trained for the crosswind landing two times on session 4 and 5.
The FDR recorded that after touchdown, initially left rudder was applied and able to
manage the aircraft heading on runway bearing and center line, afterward the right
rudder applied up to maximum and the aircraft turned to the right.
The pilots opinion the aircraft would have been veered to the left as the effect of the
cross wind from the right. An aircraft has a greater profile or side area, behind the
main landing gear than forward of it. Characteristically the crosswind, will tend to
turn or "weathervane" the aircraft into the wind and requires correct rudder
application to counter it.
During the landing roll, the wind was from the right which would tend the aircraft to
turn to the right, therefore left rudder application required. The right rudder
application was not in accordance with the characteristic of countering crosswind
effect on landing roll.
The rudder application might be caused by the pilot confusion to the crosswind effect
as stated during the interview.
The pilots had been trained for crosswind exercise two times in aircraft simulator.
However, the pilots were confused to the crosswind effect. The pilot confusion
indicated inadequate training.
It can be concluded that the incorrect rudder application to compensate the crosswind
effect had resulted in the aircraft exiting the runway. This might due to the pilot
confusion to the crosswind effect as result of inadequate training.
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3 CONCLUSION
3.1 Findings4
According to factual information during the investigation, the National
Transportation Safety Committee founded any findings as follows:
1. The aircraft was airworthy prior to departure and there was no any aircraft
systems problem reported.
2. All crew has valid licenses and medical certificates.
3. The OTM Chapter 5.5 ATR 72-500: Pilot Type Rating Training showed that the
pilots trained for the cross wind landing twice, on session 4 and session 5.
4. The aircraft departed within the weight and balance operating limit.
5. The Second in Command (SIC) acted as Pilot Flying (PF) until on final approach
when the Pilot in Command (PIC) took over control of the aircraft.
6. During approach, the pilot noticed dark and thick could which was
cumulonimbus cloud formation.
7. Controller informed the pilot that the wind condition was easterly with velocity
up to 23 knots.
8. The wind condition as recorded by AWOS changed to westerly wind and
increasing speed that related to the cumulonimbus which existed surrounding the
airport.
9. COM. 4.10.6.1 Crew Coordination during Holding stated that approach and
landing techniques and procedures to be used shall be discussed in advance, in
order to avoid errors and misunderstandings. Both pilots shall therefore
familiarize themselves thoroughly with the relevant data such as weather
conditions, holding and approach procedures runway.
10. The FDR recorded that after touchdown, initially left rudder was applied and able
to manage the aircraft heading on runway bearing and center line, afterward the
right rudder applied up to maximum and the aircraft turned to the right.
11. During the interview, the pilots explained their confusion of the effect of the
wind. They assumed that the aircraft would have been veered to the left as the
effect of right crosswind.
12. After the engines shut down the PIC went out the cockpit, then opened the crew
entrance door and disembarked the aircraft to check the outside area. The PIC
then commanded the FA to evacuate the passengers.
13. Part of the on ground evacuation procedure stated that evacuation command
conducted by the captain through public address and afterward switch off the
battery.
4 Findings are statements of all significant conditions, events or circumstances in the accident sequence. The findings are
significant steps in the accident sequence, but they are not always causal, or indicate deficiencies. Some findings point
out the conditions that pre-existed the accident sequence, but they are usually essential to the understanding of the
occurrence, usually in chronological order.
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3.2 Contributing Factors5
The investigation concluded that the incorrect rudder application to compensate the
crosswind affect had resulted in the aircraft exiting the runway. This might due to the
pilot confusion to the crosswind effect as result of inadequate training.
5 Contributing factors is defined as events that might cause the occurrence. In the case that the event did not occur then the
accident might not happen or result in a less severe occurrence.
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4 SAFETY ACTION
Following the occurrence, the PT. Wings Abadi Air management held a meeting to
discuss the occurrence and the corrective action. The meeting was attended by the
Director of Wings Air, General Manager Safety, Security and Quality, Safety
Manager, Chief Operation Safety, QMR manager, Chief Pilot ATR, Chief Operation
Training and Chief Analyst.
The meeting concluded that there was manual input from the cockpit that lead the
aircraft veered off to the right, and after the aircraft stopped, the PIC did not
command the flight attendant until the FA-1 called to the cockpit.
The meeting agreed to provide recurrent training for the flight crew and limiting the
crosswind component for PIC as pilot flying to maximum of 25 knots and the SIC to
maximum of 15 knots which was informed to pilot by a notice. (Detail of the notice
available in the appendices of this report).
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5 SAFETY RECOMMENDATIONS
The Komite Nasional Keselamatan Transportasi (KNKT) consider that the safety
actions taken by the aircraft operator were relevant to improve the issued identified
in this investigation.
In addition KNKT issued safety recommendations to address safety issues identified
during this investigation. The safety recommendations are based on the factual
information, analysis and findings of this investigation. However the operator shall
consider that the condition possibly extends to other pilots and related supporting
units within the company.
DGCA requested to ensure that the recommendations addressed to the relevant
parties are well implemented.
The safety recommendations addressed to:
5.1 PT. Wings Abadi Air
04.O-2016-86.1
To ensure the pilot understand and consistently implement the company
policies stated in the COM.
04.O-2016-87.1
To improve pilot skill and knowledge to the aerodynamic effects of crosswind
condition including the recovery technique and to consider the additional
training session of crosswind landing exercises.
04.O-2016-88.1
To improve pilot knowledge of weather effects to the flight characteristic
including the cumulonimbus effect.
04.O-2016-20.2
To ensure appropriate coordination during emergency evacuation by improving
the crew emergency training.
5.2 The Directorate General of Civil Aviation (DGCA)
04.R-2016-89.1
To oversight the operator training to ensure the achievement of the training
objectives.
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21
6 APPENDICES
6.1 Notice to Pilot
Page 30
22
6.2 The ATR Safety Note
Page 32
24
6.3 Direct Involves Parties Comments
Bureau d’Enquêtes et d’Analyses (BEA), France
NO PAGE COMMENTS
KNKT RESPONSE Extract of the Report Proposed Changes Justification
1. Cover ATR 72-500 ATR 72-212A “72-500” is a commercial
name. The model, as
identified in the EASA Type
Certificate is “72-212A”
Accepted
2. Synopsis
Page vi
There was no windshear alert
from the Ground proximity
Warning System (GPWS)
during the approach
Delete the sentence There is no windshear
alerting system on ATR 72-
212A aircraft.
Accepted
3. Synopsis
Page vi
The investigation concluded
that the contributing factors
to this serious incident was
inadequate Short Term
Memory from the absence of
discussion related to the
weather condition and
inadequate Long Term
Memory from the training
related to the input cues
assessment (diagnostic) to the
risk assessment and decision
making might have led to the
incorrect recovery action.
The investigation concluded
that the main contributing
factor to this serious incident
was the full upwind rudder
pedal application at
relatively high speed, under
crosswind conditions.
Investigating human factors
issues is very valuable.
However, the conclusion
expressed in the terms of lack
of short term memory or
inadequate long term
memory can be confusing
and not understandable by all
the readers.
Accepted with rephrase
4. §1.1 There was no wind shear Delete the sentence There is no windshear Accepted
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25
NO PAGE COMMENTS
KNKT RESPONSE Extract of the Report Proposed Changes Justification
Page 1 alert from the Ground
proximity Warning System
(GPWS) during the approach
alerting system on ATR 72-
212A aircraft.
5. §1.7
Page 8
1.7 Wreckage and Impact
Information
1.7 Wreckage and Impact
Information
Considering the damages
evidenced on the aircraft
consecutive to the incident,
and that the aircraft is back
into operations, the term
“wreckage” is not
appropriate.
Rejected. This tittle is the
standard KNKT format, even
though no information of the
wreckage.
6. §1.9.1
Page 12
Complete paragraph
“Thunderstorm formation”
Consider deleting the
paragraph
The intent of this paragraph
is unclear. If it aims at
explaining the risk of
encountering windshear, then
it should be deleted as no
windshear is evidenced
through DFDR data analysis.
Rejected
7. §1.9.2
Page 14
Extract from the ATR 72
FCOM 2.02.12 Page 1
Remove this extract and
replace by the ATR Safety
Note attached to this letter.
In February 2014, ATR has
issued the Safety Note “Be
Prepared For Crosswind
Landing” to provide guidance
to the pilots to perform
crosswind landing. This
Safety Note particularly
emphasizes the use of rudder
during landing roll that must
be smooth, mainly for any
It is good information.
However KNKT require
confirming whether this ATR
Safety Note has been
received and understood by
the pilots.
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26
NO PAGE COMMENTS
KNKT RESPONSE Extract of the Report Proposed Changes Justification
upwind input.
8. §2.2
Page 17
The thunderstorms formation,
regardless of type, goes
through three stages: …. to
the cumulonimbus which was
in view surrounding the
airport.
Consider deleting the
paragraph
Refer to comment 6 Rejected
9. §2.2
Page 17
There was no pilot discussion
recorded on the CVR to
anticipate this condition. The
only action was that the PIC
took over control of the
aircraft because of the
crosswind landing.
Add information in §1.2 or
1.8 about TEM training.
To potentially better
understand why the pilot did
not discuss the anticipated
landing conditions, the report
should highlight whether the
airline organizes Threat and
Error Management (TEM)
training for the crew.
Accepted and additional
information added to the
report on chapter 1.6.2.
Changed in the analysis.
10. §2.2
Page 17
It can be concluded that the
incorrect recovery action was
result of inadequate Short
Term Memory from the
absence of discussion related
to the weather condition and
inadequate Long Term
Memory from the training
related to the input cues
assessment (diagnostic) to
the risk assessment and
decision making.
It can be concluded that the
aircraft exiting the runway
was
the result of full upwind
rudder
pedal application at
relatively
high speed, under crosswind
conditions.
Refer to comment 3 Accepted and changed in the
analysis.
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27
NO PAGE COMMENTS
KNKT RESPONSE Extract of the Report Proposed Changes Justification
11. §3.1
Page 19
15. There were combination
of the lack of experience and
information stored affected
the pilot misinterpretation to
the effect of crosswind which
might have led to incorrect
recovery action.
Move to § 3.2 This should be considered as
a contributing factor and not
a finding.
Accepted
12. §3.2
Page 19
The absence of pilot
discussion related to the
significant information
weather particularly on the
cumulonimbus existence
which was required by the
COM, might had
reduced/absence of the Short
Term Memory and
inadequate Long Term
Memory from the training
might have led to the
misperception to the effect of
crosswind and incorrect
recovery action.
Add at the beginning of the
paragraph :
It can be concluded that the
aircraft exiting the runway
was the result of full upwind
rudder pedal application at
relatively high speed, under
crosswind conditions.
Before the contributing
factors paragraph
highlighting the absence of
pilot discussion and potential
effect on pilot memory, it is
necessary to clearly indicate
what physically led to the
aircraft exiting the runway.
Accepted and changed in the
conclusion.